AJP - Lung Journal of Applied Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Lung Cell Mol Physiol 290: L170-L178, 2006. First published August 26, 2005; doi:10.1152/ajplung.00212.2005
1040-0605/06 $8.00
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
290/1/L170    most recent
00212.2005v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (4)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Medoff, B. D.
Right arrow Articles by Luster, A. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Medoff, B. D.
Right arrow Articles by Luster, A. D.

Antibody-antigen interaction in the airway drives early granulocyte recruitment through BLT1

Benjamin D. Medoff,1,2 Andrew M. Tager,1,2 Ryan Jackobek,1 Terry K. Means,1 Lan Wang,3 and Andrew D. Luster1

1Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Massachusetts General Hospital, Charlestown; and 2Pulmonary and Critical Care Unit, and 3Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts

Submitted 12 May 2005 ; accepted in final form 19 August 2005


   ABSTRACT
TOP
 ABSTRACT
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
 DISCLOSURES
 REFERENCES
 
Antibody-antigen interactions in the airway initiate inflammation in acute asthma exacerbations. This inflammatory response is characterized by the recruitment of granulocytes into the airways. In murine models of asthma, granulocyte recruitment into the lung contributes to the development of airway hyperresponsiveness (AHR), mucus production, and airway remodeling. Leukotriene B4 is a mediator released following antigen challenge that has chemotactic activity for granulocytes, mediated through its receptor, BLT1. We investigated the role of BLT1 in granulocyte recruitment following antigen challenge. Wild-type mice and BLT1–/– mice were sensitized and challenged with ovalbumin (OVA) to induce acute allergic airway inflammation. In addition, to explore the relevance to antibody-antigen interactions, we injected OVA bound to anti-OVA IgG1 or anti-OVA IgE intratracheally into naïve wild-type and BLT1–/– mice. Cell composition of the lungs, cytokine levels, histology, and AHR were determined. After sensitization and challenge with ovalbumin, there was significantly reduced neutrophil and eosinophil recruitment into the airways of BLT1–/– mice compared with wild-type animals after one or two daily antigen challenges, but this difference was not seen after three or four daily antigen challenges. Mucus production and AHR were not affected. Intratracheal injection of OVA bound to IgG1 or IgE induced neutrophil recruitment into the airways in wild-type mice but not in the BLT1–/– mice. We conclude that BLT1 mediates early recruitment of granulocytes into the airway in response to antigen-antibody interactions in a murine model of acute asthma.

lung inflammation; asthma; lipid mediator

ACUTE ASTHMA EXACERBATIONS are life-threatening complications of allergic asthma that result in significant morbidity and health care costs (31). Inhalation of allergen initiates airway inflammation in part by binding of allergen to antigen-specific antibodies, which then bind to antibody receptors on innate immune cells, such as macrophages and mast cells. In response, these cells release numerous mediators, which initiate inflammation and induce the recruitment of neutrophils and eosinophils into the airways (5, 7, 13, 25). Granulocytes are important sources of lipid mediators, cytokines, and cytotoxic proteins and thus could play an important role in the propagation of airway inflammation and airway remodeling. Consistent with this, recent studies in murine models of asthma have demonstrated that eosinophils are crucial for the development of airway hyperresponsiveness (AHR), mucus production, and airway remodeling (8, 23, 26, 46). Furthermore, studies in humans have suggested that neutrophil and eosinophil recruitment into the airways may lead to airway fibrosis (9, 10, 14). Thus measures that inhibit the accumulation of granulocytes in the airway during asthma attacks could have profound effects on the development of airway inflammation and long-term complications of the disease.

A commonly used murine model of asthma utilizes mice sensitized and then challenged via the airway with ovalbumin (OVA) to recreate many of the pathological and physiological changes seen in acute allergic asthma exacerbations, including the recruitment of granulocytes into the airway (32, 47, 48). The initial recruitment of neutrophils has been shown to be induced in part through antigen-antibody complex stimulation of FC{gamma}RIII (47). Leukotriene B4 (LTB4) is a lipid mediator released following allergen challenge in humans (39, 41, 42, 49) and mice (20) that has potent chemotactic activity for granulocytes mediated through its G protein-coupled seven transmembrane-spanning receptor, BLT1 (18, 22, 44, 52). Because allergen-antibody complexes can stimulate mast cells (15, 19, 27) and macrophages to release LTB4 (11, 21, 36, 38), these data suggest that the LTB4/BLT1 pathway may be an important mechanism of granulocyte recruitment into the airways following allergen challenge and in acute asthma exacerbations.

In this present study we characterized the role of BLT1 in the early inflammatory response in the airway following allergen exposure. First we demonstrate that BLT1 is necessary for early eosinophil and neutrophil recruitment into the airways following antigen challenge. This recruitment defect only exists early and for the movement of the cells into the airway lumen as lung recruitment of granulocytes is preserved in the BLT1–/– mice. We then show that BLT1 is essential for granulocyte recruitment following challenge with OVA bound to IgG1 or IgE antibodies. Our findings demonstrate that the LTB4/BLT1 pathway is the major mediator of early granulocyte recruitment into the airways following exposure to allergens and is likely an important component of the early inflammatory response in acute asthma attacks. However, the early defect in granulocyte recruitment had little effect on later inflammatory events and the development of AHR and mucus production.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 GRANTS
 DISCLOSURES
 REFERENCES
 
Mice. Male 129/Sv wild-type mice and BLT1–/– mice (44) (in an 129/Sv background) were used at 6–8 wk of age. All protocols were approved by the animal studies committee at Massachusetts General Hospital.

Mouse models. Allergic airway inflammation was induced in mice as previously described (32, 43). In brief, mice were injected intraperitoneally with 10 µg of OVA (Sigma-Aldrich, St. Louis, MO) and 1 mg of aluminum hydroxide (Sigma-Aldrich) suspended in 0.5 ml of PBS (Mediatech, Herndon, VA) on days 0 and 7. Mice underwent aerosol challenge with OVA (10 mg/ml in PBS) or with PBS alone on days 14, 14–15, 14–16, or 14–17. OVA challenge was performed by placing mice in a Plexiglas box (dimensions: 22 x 23 x 14 cm) and aerosolizing OVA with a nebulizer (DeVilbiss, Health Care Division, Somerset, PA), driven by compressed air for 20 min. Mice were killed 20–24 h after the last aerosol challenge.

In some mice, AHR was measured with a whole-body plethysmograph (Buxco, Sharon, CT) as described (32). AHR was expressed as the enhanced pause (Penh), a number based on inspiratory and expiratory times and pressures that is calculated by software made by the manufacturer. The average Penh over 3 min was determined after exposure for 2 min to aerosolized PBS as a baseline. We then determined average Penh over 3 min after exposing the mice for 2 min to aerosolized methacholine (Sigma-Aldrich) at increasing concentrations (3, 6.125, 12.5, and 25 mg/ml in PBS) and expressed it as the percent change from the baseline.

For the intratracheal injections, mice were anesthetized with ketamine (80 mg/kg)-xylazine (12 mg/kg). The trachea was exposed by a ventral incision in the neck, and the trachea was injected with a 50-µl solution of either anti-OVA IgG1 (10 µg/ml, Sigma-Aldrich), anti-OVA IgE (10 µg/ml; generous gift of Dr. Lester Kobzik, Harvard School of Public Health, Boston, MA), high-purity OVA (2 mg/ml, Sigma-Aldrich), an OVA-IgG1 mixture (10 µg/ml IgG1 with 2 mg/ml OVA, incubated for 30 min at 4°C), or an OVA-IgE mixture (10 µg/ml IgE with 2 mg/ml OVA, incubated for 30 min at 4°C). Mice were allowed to recover and then were killed 20–24 h after the injection.

Bronchoalveolar lavage. Bronchoalveolar lavage (BAL) was performed at 20–24 h after the last aerosol challenge or intratracheal injection. Mice were anesthetized with a lethal injection of ketamine (100 mg/kg). The trachea was exposed and cannulated with polyethylene tubing. The lungs were lavaged with six 0.5-ml aliquots of PBS containing 0.6 mM EDTA. Lavage fluid recovered from the first 1 ml of instilled PBS/EDTA was collected separately from the rest of the BAL. Both BAL fractions were centrifuged, and the pelleted cells from both fractions were pooled for analysis. The supernatant of the BAL recovered from the first 1 ml instilled was kept frozen at –80°C for subsequent analysis. The cells from both BAL fractions were exposed for 30 s to Tris (0.014 M)/NH4Cl (0.14 M) to lyse red blood cells, and the remaining live cells, as determined by trypan blue exclusion, were washed in PBS and enumerated in a hemocytometer.

Whole lung digests. The right lung was excised and minced into small pieces with a scissors. The pieces were digested for 45 min in RPMI with 0.28 Wunsch U/ml Liberase Blendzyme (Roche, Indianapolis, IN) and 30 U/ml DNase (Sigma-Aldrich, St. Louis, MO) for 45 min at 37°C. The digested lungs were then extruded through a mesh strainer, and the collected cells were washed once with PBS. Live cells were enumerated by a hemocytometer as determined by trypan blue exclusion.

Cell differential counts. The differential cell count on cells isolated from the BAL and lung was determined by enumerating macrophages, neutrophils, eosinophils, and lymphocytes on cytocentrifuge preparations of the cells stained with Diff-Quick (Dade Behring, Newark, DE). At least 200 cells were counted on each slide.

Histopathological examination. We flushed lungs free of blood by slowly injecting 10 ml of PBS into the right ventricle before excision for all studies. The left lung was inflated with 10% buffered formalin to 25 cmH2O of pressure and transferred into vials containing 10% buffered formalin. Multiple paraffin-embedded 5-µm sections of the entire mouse lung were prepared and stained with hematoxylin-eosin and periodic acid-Schiff stain (PAS). The slides were evaluated by light microscopy, and the amount of inflammation and mucus was assessed by a pathologist blinded to the genotype of the animals. The pathologist assessed the inflammatory infiltrate around the airways, and the amount of PAS-positive staining on three whole lung sections of the left lung from each mouse was evaluated. Each set of three sections was given a score of 0–4 for inflammation (0 = no inflammation, 4 = severe inflammation) and 0–4 for PAS-positive staining (0 = no PAS-positive cells, 4 = high numbers of PAS-positive cells).

RNA analysis of lung chemokine expression. RNA was purified with a purification column (RNeasy; Qiagen, Valencia, CA). After a DNase step, 1 µg of RNA was converted to cDNA (Applied Biosystems, Warrington, UK). Specific primers used for sequence detection of message for the chemokine genes are listed on the website http://www.immunologynet.org/. Samples underwent amplification in the presence of SYBR green (Applied Biosystems). The reaction was analyzed in real-time during amplification by the PCR machine (MX-4000; Stratagene, La Jolla, CA).

Granulocyte chemotaxis. Granulocytes were isolated from bone marrow isolated from wild-type and BLT1–/– mice by gradient centrifugation as described (2). Isolated cells were stained with Calcein (Molecular Probes, Eugene OR) according to the manufacturer's protocol. BAL fluid (30 µl) was placed into the bottom wells of a 96-well chemotaxis plate (Neuroprobe, Gaithersburg, MD), and 50 µl of labeled granulocytes (5.0 x 106 cells/ml in HBSS) were placed in the top wells. The apparatus was incubated at 37°C for 2 h. Cell migration into the bottom chamber was quantified by the fluorescence at 540 nm and comparison to known amounts of labeled cells.

BAL LTB4, CXCL1, CXCL2, OVA-specific IgG, and IgE determinations. BAL LTB4, CXCL1, and CXCL2 levels were assessed by commercially available kits (Cayman Chemical, Ann Arbor, MI; R&D Systems, Minneapolis, MN) according to the manufacturer's instructions. BAL OVA-specific IgE and IgG concentrations were measured by ELISA as described (28).

Data analysis. Data are expressed as means ± SE. Differences in results were considered to be statistically significant when P < 0.05 by a Student's t-test or ANOVA.


   RESULTS
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 GRANTS
 DISCLOSURES
 REFERENCES
 
BAL granulocyte recruitment is reduced early after antigen challenge. We determined the number of eosinophils and neutrophils in the BAL taken from OVA-immunized wild-type or BLT1–/– mice after 1, 2, 3, or 4 daily OVA challenges. There was a statistically significant reduction in the numbers of eosinophils (18-fold) and neutrophils (32-fold) in the BAL of BLT1–/– mice compared with wild-type mice after one OVA challenge (Fig. 1, A and B). After two daily OVA challenges there continued to be a significant reduction in both eosinophil and neutrophil recruitment into the airways (three- and fivefold respectively). However, this difference was not seen with repetitive challenges on days 3 and 4 (Fig. 1, A and B) or 3 days after a single OVA challenge (data not shown). These data suggest that BLT1 mediates early granulocyte recruitment into the airways, whereas alternative mediators are induced later in response to antigen challenge.



View larger version (19K):
[in this window]
[in a new window]
  		Fig. 1. Granulocyte recruitment into the airways. A: eosinophil recruitment into the bronchoalveolar lavage (BAL) of wild-type and BLT1–/– mice after 1, 2, 3, and 4 daily ovalbumin (OVA) challenges (n = 8 mice per group). B: neutrophil recruitment into the BAL of wild-type and BLT1–/– mice after 1, 2, 3, and 4 daily OVA challenges (n = 8 mice per group).

 
Lung granulocyte recruitment is not different in BLT1–/– mice following antigen challenge. We also determined the number of eosinophils and neutrophils recruited into the lung tissue of immunized wild-type or BLT1–/– mice following one, two, three, or four daily OVA challenges. As opposed to the BAL data, we did not see any difference in the number of lung eosinophils or neutrophils between the two groups (Fig. 2, A and B). Lung histology confirmed the presence of peribronchial eosinophils and neutrophils in both wild-type and BLT1–/– mice after one OVA challenge (Fig. 3, A and B). Evaluation of the level of inflammation around the airways based on blinded scoring of histological sections as outlined in MATERIALS AND METHODS was also not significantly different between the two mouse groups (data not shown). These data suggest a selective role for BLT1 in the recruitment of granulocytes into the airway and alternative mechanisms for lung recruitment of these cells.



View larger version (14K):
[in this window]
[in a new window]
  		Fig. 2. Granulocyte recruitment into the lungs. A: eosinophil recruitment into the lung of wild-type and BLT1–/– mice after 1 and 2 OVA challenges (n = 8 mice per group). B: neutrophil recruitment into the lung of wild-type and BLT1–/– mice after 1 and 2 OVA challenges (n = 8 mice per group).

 


View larger version (114K):
[in this window]
[in a new window]
  		Fig. 3. Representative histology. Representative (of n = 8 mice/group) high-magnification views (x400) of an airway from a wild-type mouse (A) and a BLT1–/– mouse (B) 24 h after a single OVA challenge. Eosinophils (black arrow) have accumulated around the airways in both mice.

 
AHR and mucus production were not different between wild-type and BLT1–/– mice. To determine the effect of an airway granulocyte recruitment defect on the phenotypic changes seen in asthma we evaluated the production of mucus and the development of AHR. Mucus production as assessed by blinded scoring of PAS staining of lung sections as outlined in MATERIALS AND METHODS was not different between the two mouse groups (data not shown). AHR was measured in these mice using methacholine-induced changes in the Penh, a noninvasive surrogate for airway resistance (16). After one, two, three, or four daily OVA challenges, immunized wild-type and BLT1–/– mice had similar elevations in their Penh following methacholine challenge (Fig. 4, A and B, and data not shown).



View larger version (19K):
[in this window]
[in a new window]
  		Fig. 4. Airway hyperreactivity. A: airway hyperreactivity (AHR) in normal saline-challenged wild-type and BLT1–/– mice (control, n = 6 mice each), OVA-challenged wild-type mice, and OVA-challenged BLT1–/– mice (n = 8 mice each). AHR was measured after 1 OVA challenge. B: AHR in normal saline-challenged wild-type and BLT1–/– mice (control, n = 6 mice each), OVA-challenged wild-type mice, and OVA-challenged BLT1–/– mice (n = 8 mice each). AHR was measured after 2 OVA challenges. AHR is expressed as the percent change in the average enhanced pause (Penh) over baseline in the 3 min following a 2-min exposure to increasing concentrations of aerosolized methacholine in PBS.

 
BAL fluid from OVA-immunized and -challenged animals induced more chemotaxis for granulocytes from wild-type mice compared with those from BLT1–/– mice. We wanted to better define the mechanism of the granulocyte recruitment defect seen in these experiments. First we attempted to measure LTB4 levels in the lavage fluid from wild-type and BLT1–/– mice after one or two OVA challenges. The levels were at or below the limit of detection of the assay as reported by others (37) (data not shown). This did not rule out a role for LTB4 as it has potent activity at low concentrations, so we used an in vitro chemotaxis assay as a functional test of LTB4 activity in the BAL. Granulocytes were isolated from the bone marrow of wild-type and BLT1–/– mice by gradient separation. This preparation yielded ~80% early granulocyte precursors as assessed by cytospins (data not shown). BAL fluid from wild-type and BLT1–/– mice that had been sensitized and challenged with OVA for 2 days was used to induce chemotaxis of the isolated cells. There was a significant decrease in chemotaxis of the BLT1–/– granulocytes compared with wild-type granulocytes from BAL from both wild-type and BLT1–/– mice (Fig. 5A). Interestingly, BLT1–/– BAL fluid had less chemotactic activity for wild-type granulocytes than BAL from wild-type mice. Because granulocytes are a major source of LTB4 (53), the defect in granulocyte recruitment into the airways seen in the BLT1–/– mice could lead to reduced LTB4 levels in the BAL compared with BAL from wild-type mice.



View larger version (19K):
[in this window]
[in a new window]
  		Fig. 5. BAL fluid granulocyte chemotactic potential and chemokine levels. A: average number of granulocytes from wild-type or BLT1–/– mice that migrated into the wells of a chemotaxis plate in response to BAL fluid isolated from wild-type or BLT1–/– mice after 2 daily OVA challenges (average of 6 BAL samples, each performed in triplicate). B: RNA expression levels of CXCL1 and CXCL2 in the lungs of wild-type and BLT1–/– mice after OVA immunization and challenge with 1 or 2 daily OVA nebulizations (n = 7 mice per group). The differences were not significant. C: protein levels of CXCL1 and CXCL2 in the BAL fluid taken from wild-type and BLT1–/– mice after OVA immunization and challenge with 1 or 2 daily OVA nebulizations (n = 7 mice per group). The differences were not significant.

 
Neutrophil chemokine expression in the lung. Other neutrophil-specific chemokines are expressed in the murine model of asthma such as CXCL1/KC and CXCL2/MIP-2 (47). To see if the expression of these chemokines was affected by disruption in BLT1 signaling we measured the RNA expression of these chemokines in lungs harvested from OVA-sensitized and -challenged BLT1–/– and wild-type mice. After one or two daily OVA challenges, analysis of the RNA expression of CXCL1 and CXCL2 in the lungs showed no statistically significant differences in both groups of mice (Fig. 5B). We also measured the protein levels of these chemokines in the BAL from these same mice and found no differences in the protein levels of CXCL1 and CXCL2 between BLT1–/– and wild-type mice (Fig. 5C). Protein levels of these chemokines were both upregulated in the BAL compared with unchallenged mice (undetectable levels, data not shown). We did find a higher concentration of CXCL1 than CXCL2 in the BAL, which differed from the RNA expression data. This difference may be a reflection of the different compartments of the lung in that the BAL samples only from the airways, whereas the RNA data represented lung parenchyma expression as well as the airway. Despite the differences between the RNA and protein levels both assays demonstrated that BLT1–/– mice make similar amounts of CXCL1 and CXCL2 compared with wild-type animals.

BAL levels of OVA-specific IgG1 and IgE antibodies are increased in immunized wild-type and BLT1–/– animals. Our hypothesis is that antigen-antibody interactions in the airway lead to BLT1-mediated granulocyte recruitment. Thus we wanted to confirm that OVA-specific antibodies were present in both wild-type and BLT1–/– mice at equal levels. We measured the levels of OVA-specific IgG1 and IgE in BAL fluid isolated from unimmunized mice and OVA immunized wild-type and BLT1–/– mice with an ELISA. There was a significant increase in the amount of OVA-specific IgG1 and IgE in the BAL of immunized wild-type and BLT1–/– mice compared with naïve mice, in which the levels of OVA-specific antibodies were undetectable (Fig. 6, A and B). There was no significant difference in antibody levels, however, between the wild-type and BLT1–/– animals.



View larger version (15K):
[in this window]
[in a new window]
  		Fig. 6. Antigen-specific antibody production in the airway. A: amount of OVA-specific IgG in BAL samples from naïve or immunized wild-type and BLT1–/– mice as measured by absorbance (n = 3 mice per group). Levels of antibodies in naïve mice were not detected. B: amount of OVA-specific IgE in BAL samples from naïve or immunized wild-type BLT1–/– mice as measured by absorbance (n = 3 mice per group). Levels of antibodies in naïve mice were not detected. N.D., not detected.

 
OVA-IgG1 and OVA-IgE antigen-antibody complexes induce granulocyte recruitment in wild-type mice but not in BLT1–/– mice. Finally, to focus the stimulus for granulocyte recruitment into the airway to antibody-antigen induced interactions, we combined OVA with OVA-specific IgG1 and IgE antibodies and then injected the mixture into the tracheae of naïve wild-type and BLT1–/– mice. These complexes induced prominent neutrophil recruitment into the airways of the wild-type animals 1 day after injection (Fig. 7). A previous study utilizing the same model had shown that granulocyte recruitment peaked at ~10–20 h and then disappeared at 48 h, so later time points were not checked (47). Injection of OVA alone, IgG1 alone, or IgE alone did not induce significant neutrophil recruitment into the BAL. The OVA-IgG1 mixture stimulated more granulocyte recruitment than the OVA-IgE mixture in wild-type mice. When the antibody-antigen mixtures were injected into BLT1–/– mice, however, there was dramatic and significant reduction in neutrophil recruitment into the airways (Fig. 7). Granulocyte recruitment after injection of OVA-IgG1 was reduced by eightfold, and after injection of OVA-IgE was reduced by over 70-fold in BLT1–/– mice compared with the wild-type mice. In fact, the number of neutrophils in the airways of BLT1–/– mice after injection of OVA-IgE was similar to the number after injection of OVA or IgE alone. These data provide strong evidence supporting a role for BLT1 in granulocyte recruitment following antigen-antibody interactions in the airway. The LTB4/BLT1 pathway seems to stimulate the majority of the granulocyte recruitment induced by IgG1-mediated stimulation and nearly all of the recruitment induced by IgE.



View larger version (9K):
[in this window]
[in a new window]
  		Fig. 7. Antigen-antibody complex induced neutrophil recruitment to the airway. The number of neutrophils recruited into the BAL is shown in wild-type and BLT1–/– mice 20–24 h after intratracheal injection of OVA-IgG1 complexes, OVA-IgE complexes, OVA alone, IgG1 alone, and IgE alone (n = 6 mice per group).

 

   DISCUSSION
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
GRANTS
 DISCLOSURES
 REFERENCES
 
Acute asthma exacerbations remain the major cause of morbidity and mortality in patients with asthma. A large number of exacerbations are caused by exposure to allergens in sensitized individuals. In the minutes following allergen inhalation, mast cells and alveolar macrophages are stimulated to degranulate via binding to IgE and IgG antibodies complexed to antigen. The released mediators induce bronchoconstriction, edema, and the recruitment of granulocytes into the airways (4, 17). Although mechanistic studies have identified an essential role for lymphocyte recruitment in the establishment of asthma (28–30, 33), recently there has been increasing realization of the importance of granulocytes in the pathogenesis of this disorder (8, 23, 26, 46, 50). Eosinophil recruitment into the lung in particular has been shown to be crucial for the development of AHR and mucus production in murine models of asthma, whereas neutrophil recruitment into the lung has been linked to severe asthma and fatal asthma attacks (1, 50). In addition to mediating acute changes in the airway, granulocytes may help establish a chronic inflammatory state and mediate some of the late complications of disease such as airway remodeling (10, 14, 23).

In the present study we use a model of acute asthma to demonstrate that early airway granulocyte recruitment was dependent on BLT1 expression. This recruitment was specific to the airway as lung recruitment of granulocytes was preserved with disruption of BLT1 expression. Furthermore, the effect was limited to the early inflammatory response and did not influence late inflammatory events, suggesting that additional mechanisms are activated later after antigen challenge. Mucus production and AHR were not diminished in BLT1–/– mice. We suspect that the preserved recruitment of granulocytes and lymphocytes into the lung was sufficient to induce AHR and mucus production. The observed differences were solely due to disruption of BLT1 signaling and not due to disruption of the low-affinity LTB4 receptor (BLT2) as BLT2 is not expressed in mouse leukocytes or in the lung (24).

We then performed a series of experiments to explore the mechanism of this recruitment defect. In an in vitro chemotaxis assay, BAL fluid isolated from sensitized and challenged animals was chemotactic for isolated murine granulocytes from wild-type animals but less so for granulocytes from BLT1–/– mice, suggesting that the chemotactic activity in the BAL was mediated in part by LTB4. Interestingly BAL fluid isolated from sensitized and challenged BLT1–/– mice induced less granulocyte chemotaxis than BAL fluid from wild-type mice. As mentioned in RESULTS, granulocytes are a major source of LTB4 (53), and LTB4 may stimulate more 5-lipoxygenase activity in neutrophils (40). Thus increased neutrophil recruitment into the airway would be expected to amplify LTB4 production and increase the chemotactic potency of the BAL. We next demonstrated that the recruitment defect was not due to differences in the expression of two other neutrophil-specific chemoattractants, CXCL1 and CXCL2. To confirm that the recruitment defect was from the absence of BLT1 on granulocytes and not due to differences in antibody production in the BLT1–/– mice we demonstrated equal levels of OVA-specific IgG and IgE in the airways of immunized and sensitized wild-type and BLT1–/– mice. Finally, when OVA bound to IgG1 or IgE was injected into the airways of nonsensitized mice there was BLT1-dependent recruitment of neutrophils into the airway. This did not occur if the antibodies alone or OVA alone were injected. Together, these data demonstrate that early granulocyte recruitment after antigen challenge results from antigen-antibody-induced release of LTB4 into the airways and that BLT1 is an important mediator of granulocyte recruitment in asthma after allergen inhalation.

Our findings are consistent with prior studies that demonstrated early antigen-specific granulocyte recruitment into the airways following allergen challenge. In these experiments utilizing murine models of allergic airway disease, IgG-allergen and IgE-allergen immune complexes were able to induce granulocyte recruitment into the airways presumably through the release of various chemoattractants (47, 54). In one of the studies, upregulation of the neutrophil-specific chemokines CXCL1 and CXCL2 was found following challenge with allergen-antibody complexes (47). However, LTB4 liberation was not examined, and it was not definitively demonstrated that these chemokines were the crucial mediators of neutrophil recruitment into the airway. Because allergen-antibody complexes can stimulate mast cells (15, 19, 27) and macrophages to release LTB4 (11, 21, 36, 38), our data clearly link the early recruitment of granulocytes following allergen challenge to the LTB4/BLT1 pathway. Although our study suggests that CXCL1 and CXCL2 do not mediate early neutrophil recruitment into the airway following challenge with antigen-antibody complexes, it does not rule out a possible role for CXCL1 and CXCL2 in the early recruitment of neutrophils into the lung parenchyma. In addition, the granulocyte recruitment that occurred at later time points may have been due to the liberation of other chemoattractants, such as CXCL1, CXCL2, and the eotaxins (CCL11 and CCL24). Thus our data provide a mechanism for the granulocyte recruitment seen in the early inflammatory response following antigen exposure and during acute asthma exacerbations.

There are three prior papers reporting on the role of BLT1 in asthma. In our previous study we demonstrated similar findings for effector T cell recruitment into the airway following allergen challenge of sensitized mice (43). In these experiments, early T cell recruitment into the airway was dependent on BLT1 expression on T cells. Lung recruitment of lymphocytes and late events were not influenced by disruption of BLT1. These data are consistent with a two-compartment model of lung recruitment where different factors control recruitment of cells into the lung parenchyma vs. the airways. The findings of our studies, along with those of Taube et al. (47), suggest a coordinated process following antigen challenge whereby CXCL1 and CXCL2 recruit neutrophils into the lung and BLT1 mediates their subsequent movement into the air spaces early in the inflammatory process.

More recently it has been demonstrated that BLT1 expression on CD8+ effector T cells helps establish allergic inflammation and AHR in an adoptive transfer model of asthma (35). In these experiments, airway inflammation and AHR were reduced in immunized and challenged CD8–/– mice compared with wild-type animals. Transfer of in vivo primed wild-type CD8+ T cells or in vitro polarized transgenic OVA-specific CD8+ T cells into sensitized and challenged CD8–/– mice was able to reestablish airway inflammation and AHR, but this did not occur if the transferred CD8+ T cells were deficient in BLT1. In a subsequent study, BLT1–/– mice in a BALB/c background were used, in a similar model to the one used in the studies presented here, to demonstrate that BLT1 was important for the establishment of AHR and mucus production after three OVA aerosol challenges (34). It was shown that the reduced AHR and mucus production in BLT1–/– mice were the result of a defect in the recruitment of IL-13-producing T cells into the airways. Similar to our findings they did not see a defect in granulocyte recruitment after three OVA challenges. Importantly, the authors did not look at earlier time points or specifically at the mechanisms of early granulocyte recruitment. Unlike these last two studies, we were not able to demonstrate a decrease in AHR or mucus production in OVA-sensitized and -challenged BLT1–/– mice. However, in the two prior studies the BLT1–/– mice used were in different genetic backgrounds, and in the first study the model used was different, all of which can influence the development of AHR and allergic airway inflammation (6, 45, 51). Finally, the other studies directly measured airway resistance, whereas in our study AHR was measured noninvasively by whole body plethysmography and the Penh. The ability of this technique to assess changes in airway resistance is controversial (3), and it is possible that direct measures of airway resistance would disclose more subtle differences.

Although the disruption of BLT1 signaling had profound effects on early airway inflammation in this murine model of asthma, these effects were not sustained, and AHR and mucus production were apparently not modulated. Consistent with this, in a study of allergic asthmatics, administration of a BLT1 antagonist reduced neutrophil recruitment into the airway following allergen challenge but did not affect AHR (12). This suggests that although inhibition of BLT1 may reduce the amount of granulocytes recruited into the airway, this may not be of great benefit in the treatment of people with asthma. Our data clearly demonstrate an important inflammatory mechanism in the development of airway inflammation. The fact that there is no effect on the overall asthma phenotype suggests that the mechanisms that lead to airway inflammation in asthma are complex and redundant and that therapeutic strategies that target the LTB4/BLT1 pathway in asthma may need to be combined with other therapies. However, these studies do not address the potential benefits of long-term inhibition of BLT1. In addition, there are some subtypes of asthma that have more neutrophilic predominant inflammation (50), and it is possible that the LTB4/BLT1 pathway plays a more important role in these forms of airway inflammation.


   GRANTS
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
DISCLOSURES
 REFERENCES
 
This work was supported by National Institute of Allergy and Infectious Diseases Grants F32 AI-50399 (to B. D. Medoff), R01 AI-40618-08, and R01 AI-050892 (to A. D. Luster).


   DISCLOSURES
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
 DISCLOSURES
REFERENCES
 
This work was also supported by a Medical School Grant from Merck (to B. D. Medoff).


   ACKNOWLEDGMENTS
 
The authors thank Andrew Carafone and Carol Leary for technical support with this research.

Present address for Lan Wang: Chilton Memorial Hospital, 97 West Pkwy., Pompton Plains, NJ 07444-1696.


   FOOTNOTES
 

Address for reprint requests and other correspondence: A. D. Luster, Center for Immunology and Inflammatory Diseases, Div. of Rheumatology, Allergy and Immunology, Massachusetts General Hospital, CNY 8301, 149 13th St., Charlestown, MA 02129 (e-mail: luster.andrew{at}mgh.harvard.edu)

The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.


   REFERENCES
TOP
 ABSTRACT
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 GRANTS
 DISCLOSURES
 REFERENCES
 

  1. European Network for Understanding Mechanisms of Severe Asthma. Cross-sectional European multicentre study of the clinical phenotype of chronic severe asthma. Eur Respir J 22: 470–477, 2003.[Abstract/Free Full Text]
  2. Allport JR, Lim YC, Shipley JM, Senior RM, Shapiro SD, Matsuyoshi N, Vestweber D, and Luscinskas FW. Neutrophils from MMP-9- or neutrophil elastase-deficient mice show no defect in transendothelial migration under flow in vitro. J Leukoc Biol 71: 821–828, 2002.[Abstract/Free Full Text]
  3. Bates J, Irvin C, Brusasco V, Drazen J, Fredberg J, Loring S, Eidelman D, Ludwig M, Macklem P, Martin J, Milic-Emili J, Hantos Z, Hyatt R, Lai-Fook S, Leff A, Solway J, Lutchen K, Suki B, Mitzner W, Pare P, Pride N, and Sly P. The use and misuse of Penh in animal models of lung disease. Am J Respir Cell Mol Biol 31: 373–374, 2004.[Free Full Text]
  4. Boyce JA. The role of mast cells in asthma. Prostaglandins Leukot Essent Fatty Acids 69: 195–205, 2003.[CrossRef][Web of Science][Medline]
  5. Bradley BL, Azzawi M, Jacobson M, Assoufi B, Collins JV, Irani AM, Schwartz LB, Durham SR, Jeffery PK, and Kay AB. Eosinophils, T-lymphocytes, mast cells, neutrophils, and macrophages in bronchial biopsy specimens from atopic subjects with asthma: comparison with biopsy specimens from atopic subjects without asthma and normal control subjects and relationship to bronchial hyperresponsiveness. J Allergy Clin Immunol 88: 661–674, 1991.[CrossRef][Web of Science][Medline]
  6. Brewer JP, Kisselgof AB, and Martin TR. Genetic variability in pulmonary physiological, cellular, and antibody responses to antigen in mice. Am J Respir Crit Care Med 160: 1150–1156, 1999.[Abstract/Free Full Text]
  7. Busse WW and Lemanske RF Jr. Asthma. N Engl J Med 344: 350–362, 2001.[Free Full Text]
  8. Cho JY, Miller M, Baek KJ, Han JW, Nayar J, Lee SY, McElwain K, McElwain S, Friedman S, and Broide DH. Inhibition of airway remodeling in IL-5-deficient mice. J Clin Invest 113: 551–560, 2004.[CrossRef][Web of Science][Medline]
  9. Chu HW, Trudeau JB, Balzar S, and Wenzel SE. Peripheral blood and airway tissue expression of transforming growth factor beta by neutrophils in asthmatic subjects and normal control subjects. J Allergy Clin Immunol 106: 1115–1123, 2000.[CrossRef][Web of Science][Medline]
  10. Cundall M, Sun Y, Miranda C, Trudeau JB, Barnes S, and Wenzel SE. Neutrophil-derived matrix metalloproteinase-9 is increased in severe asthma and poorly inhibited by glucocorticoids. J Allergy Clin Immunol 112: 1064–1071, 2003.[CrossRef][Web of Science][Medline]
  11. DuBourdieu DJ and Morgan DW. Multiple pathways for signal transduction in the regulation of arachidonic acid metabolism in rat peritoneal macrophages. Biochim Biophys Acta 1054: 326–332, 1990.[Medline]
  12. Evans DJ, Barnes PJ, Spaethe SM, van Alstyne EL, Mitchell MI, and O'Connor BJ. Effect of a leukotriene B4 receptor antagonist, LY293111, on allergen induced responses in asthma. Thorax 51: 1178–1184, 1996.[Abstract/Free Full Text]
  13. Fahy JV, Kim KW, Liu J, and Boushey HA. Prominent neutrophilic inflammation in sputum from subjects with asthma exacerbation. J Allergy Clin Immunol 95: 843–852, 1995.[CrossRef][Web of Science][Medline]
  14. Flood-Page P, Menzies-Gow A, Phipps S, Ying S, Wangoo A, Ludwig MS, Barnes N, Robinson D, and Kay AB. Anti-IL-5 treatment reduces deposition of ECM proteins in the bronchial subepithelial basement membrane of mild atopic asthmatics. J Clin Invest 112: 1029–1036, 2003.[CrossRef][Web of Science][Medline]
  15. Freeland HS, Schleimer RP, Schulman ES, Lichtenstein LM, and Peters SP. Generation of leukotriene B4 by human lung fragments and purified human lung mast cells. Am Rev Respir Dis 138: 389–394, 1988.[Web of Science][Medline]
  16. Hamelmann E, Schwarze J, Takeda K, Oshiba A, Larsen GL, Irvin CG, and Gelfand EW. Noninvasive measurement of airway responsiveness in allergic mice using barometric plethysmography. Am J Respir Crit Care Med 156: 766–775, 1997.[Abstract/Free Full Text]
  17. Hamelmann E, Tadeda K, Oshiba A, and Gelfand EW. Role of IgE in the development of allergic airway inflammation and airway hyperresponsiveness–a murine model. Allergy 54: 297–305, 1999.[CrossRef][Web of Science][Medline]
  18. Haribabu B, Verghese MW, Steeber DA, Sellars DD, Bock CB, and Snyderman R. Targeted disruption of the leukotriene B(4) receptor in mice reveals its role in inflammation and platelet-activating factor-induced anaphylaxis. J Exp Med 192: 433–438, 2000.[Abstract/Free Full Text]
  19. Heavey DJ, Ernst PB, Stevens RL, Befus AD, Bienenstock J, and Austen KF. Generation of leukotriene C4, leukotriene B4, and prostaglandin D2 by immunologically activated rat intestinal mucosa mast cells. J Immunol 140: 1953–1957, 1988.[Abstract/Free Full Text]
  20. Henderson WR Jr, Lewis DB, Albert RK, Zhang Y, Lamm WJ, Chiang GK, Jones F, Eriksen P, Tien YT, Jonas M, and Chi EY. The importance of leukotrienes in airway inflammation in a mouse model of asthma. J Exp Med 184: 1483–1494, 1996.[Abstract/Free Full Text]
  21. Hsueh W, Gonzalez-Crussi F, and Henderson S. LTB4 production and lysosomal enzyme release by rat alveolar macrophages: effects of phagocytosis, receptor binding, and ionophore stimulation. Exp Lung Res 13: 385–399, 1987.[Web of Science][Medline]
  22. Huang WW, Garcia-Zepeda EA, Sauty A, Oettgen HC, Rothenberg ME, and Luster AD. Molecular and biological characterization of the murine leukotriene B4 receptor expressed on eosinophils. J Exp Med 188: 1063–1074, 1998.[Abstract/Free Full Text]
  23. Humbles AA, Lloyd CM, McMillan SJ, Friend DS, Xanthou G, McKenna EE, Ghiran S, Gerard NP, Yu C, Orkin SH, and Gerard C. A Critical role for eosinophils in allergic airways remodeling. Science 305: 1776–1779, 2004.[Abstract/Free Full Text]
  24. Iizuka Y, Yolomizo T, Terawaki K, Komine M, Tamaki K, and Shimizu T. Characterization of a mouse second leukotriene B4 receptor, mBLT2-BLT2-dependent ERK activation and cell migration of primary mouse keratinocytes. J Biol Chem 280: 24816–24823, 2005.[Abstract/Free Full Text]
  25. Koh YY, Dupuis R, Pollice M, Albertine KH, Fish JE, and Peters SP. Neutrophils recruited to the lungs of humans by segmental antigen challenge display a reduced chemotactic response to leukotriene B4. Am J Respir Cell Mol Biol 8: 493–499, 1993.[Web of Science][Medline]
  26. Lee JJ, Dimina D, Macias MP, Ochkur SI, McGarry MP, O'Neill KR, Protheroe C, Pero R, Nguyen T, Cormier SA, Lenkiewicz E, Colbert D, Rinaldi L, Ackerman SJ, Irvin CG, and Lee NA. Defining a link with asthma in mice congenitally deficient in eosinophils. Science 305: 1773–1776, 2004.[Abstract/Free Full Text]
  27. Levi-Schaffer F, Austen KF, Caulfield JP, Hein A, Gravallese PM, and Stevens RL. Co-culture of human lung-derived mast cells with mouse 3T3 fibroblasts: morphology and IgE-mediated release of histamine, prostaglandin D2, and leukotrienes. J Immunol 139: 494–500, 1987.[Abstract]
  28. MacLean JA, Ownbey R, and Luster AD. T cell-dependent regulation of eotaxin in antigen-induced pulmonary eosinophila. J Exp Med 184: 1461–1469, 1996.[Abstract/Free Full Text]
  29. Mathew A, MacLean JA, DeHaan E, Tager AM, Green FH, and Luster AD. Signal transducer and activator of transcription 6 controls chemokine production and T helper cell type 2 cell trafficking in allergic pulmonary inflammation. J Exp Med 193: 1087–1096, 2001.[Abstract/Free Full Text]
  30. Mathew A, Medoff BD, Carafone AD, and Luster AD. Cutting edge: Th2 cell trafficking into the allergic lung is dependent on chemoattractant receptor signaling. J Immunol 169: 651–655, 2002.[Abstract/Free Full Text]
  31. McFadden ER Jr. Acute severe asthma. Am J Respir Crit Care Med 168: 740–759, 2003.[Abstract/Free Full Text]
  32. Medoff BD, Sauty A, Tager AM, Maclean JA, Smith RN, Mathew A, Dufour JH, and Luster AD. IFN-gamma-inducible protein 10 (CXCL10) contributes to airway hyperreactivity and airway inflammation in a mouse model of asthma. J Immunol 168: 5278–5286, 2002.[Abstract/Free Full Text]
  33. Miyahara N, Swanson BJ, Takeda K, Taube C, Miyahara S, Kodama T, Dakhama A, Ott VL, and Gelfand EW. Effector CD8+ T cells mediate inflammation and airway hyper-responsiveness. Nat Med 10: 865–869, 2004.[CrossRef][Web of Science][Medline]
  34. Miyahara N, Takeda K, Miyahara S, Matsubara S, Koya T, Joetham A, Krishnan E, Dakhama A, Haribabu B, and Gelfand EW. Requirement for leukotriene B4 receptor 1 in allergen-induced airway hyperresponsiveness. Am J Respir Crit Care Med 172: 161–167, 2005.[Abstract/Free Full Text]
  35. Miyahara N, Takeda K, Miyahara S, Taube C, Joetham A, Koya T, Matsubara S, Dakhama A, Tager AM, Luster AD, and Gelfand EW. Leukotriene B4 (BLT1) is essential for allergen-mediated recruitment of CD8+ T cells and airway hyperresponsiveness. J Immunol 174: 4979–4984, 2005.[Abstract/Free Full Text]
  36. Rankin JA, Schrader CE, Smith SM, and Lewis RA. Recombinant interferon-gamma primes alveolar macrophages cultured in vitro for the release of leukotriene B4 in response to IgG stimulation. J Clin Invest 83: 1691–1700, 1989.[Web of Science][Medline]
  37. Richards IM, Sun FF, Taylor BM, Shields SK, Griffin RL, Morris J, Wishka DG, Smith HW, Johnson RA, and Dunn CJ. Contribution of leukotriene B4 to airway inflammation and the effect of antagonists. Ann NY Acad Sci 629: 274–287, 1991.[Web of Science][Medline]
  38. Robbins RA, Gossman GL, Allington LA, Kendall TJ, Stull TW, and Rennard SI. Modulation of alveolar macrophage leukotriene B4 released by complement component C5. J Lab Clin Med 115: 497–503, 1990.[Web of Science][Medline]
  39. Sampson AP, Castling DP, Green CP, and Price JF. Persistent increase in plasma and urinary leukotrienes after acute asthma. Arch Dis Child 73: 221–225, 1995.[Abstract/Free Full Text]
  40. Serio KJ, Baker JR, Ring WL, Riddick CA, and Bigby TD. Leukotriene B4 costimulates 5-lipoxygenase activity in neutrophils via increased 5-lipoxygenase translocation. Am J Physiol Cell Physiol 272: C1329–C1334, 1997.[Abstract/Free Full Text]
  41. Shindo K, Fukumura M, and Miyakawa K. Leukotriene B4 levels in the arterial blood of asthmatic patients and the effects of prednisolone. Eur Respir J 8: 605–610, 1995.[Abstract]
  42. Shindo K, Miyakawa K, and Fukumura M. Plasma levels of leukotriene B4 in asthmatic patients. Int J Tissue React 15: 181–184, 1993.[Web of Science][Medline]
  43. Tager AM, Bromley SK, Medoff BD, Islam SA, Bercury SD, Friedrich EB, Carafone AD, Gerszten RE, and Luster AD. Leukotriene B4 receptor BLT1 mediates early effector T cell recruitment. Nat Immun 4: 982–990, 2003.[CrossRef][Web of Science][Medline]
  44. Tager AM, Dufour JH, Goodarzi K, Bercury SD, von Andrian UH, and Luster AD. BLTR mediates leukotriene B(4)-induced chemotaxis and adhesion and plays a dominant role in eosinophil accumulation in a murine model of peritonitis. J Exp Med 192: 439–446, 2000.[Abstract/Free Full Text]
  45. Takeda K, Haczku A, Lee JJ, Irvin CG, and Gelfand EW. Strain dependence of airway hyperresponsiveness reflects differences in eosinophil localization in the lung. Am J Physiol Lung Cell Mol Physiol 281: L394–L402, 2001.[Abstract/Free Full Text]
  46. Tanaka H, Komai M, Nagao K, Ishizaki M, Kajiwara D, Takatsu K, Delespesse G, and Nagai H. Role of interleukin-5 and eosinophils in allergen-induced airway remodeling in mice. Am J Respir Cell Mol Biol 31: 62–68, 2004.[Abstract/Free Full Text]
  47. Taube C, Dakhama A, Rha YH, Takeda K, Joetham A, Park JW, Balhorn A, Takai T, Poch KR, Nick JA, and Gelfand EW. Transient neutrophil infiltration after allergen challenge is dependent on specific antibodies and Fc gamma III receptors. J Immunol 170: 4301–4309, 2003.[Abstract/Free Full Text]
  48. Tomkinson A, Cieslewicz G, Duez C, Larson KA, Lee JJ, and Gelfand EW. Temporal association between airway hyperresponsiveness and airway eosinophilia in ovalbumin-sensitized mice. Am J Respir Crit Care Med 163: 721–730, 2001.[Abstract/Free Full Text]
  49. Wardlaw AJ, Hay H, Cromwell O, Collins JV, and Kay AB. Leukotrienes, LTC4 and LTB4, in bronchoalveolar lavage in bronchial asthma and other respiratory diseases. J Allergy Clin Immunol 84: 19–26, 1989.[CrossRef][Web of Science][Medline]
  50. Wenzel SE, Szefler SJ, Leung DY, Sloan SI, Rex MD, and Martin RJ. Bronchoscopic evaluation of severe asthma. Persistent inflammation associated with high dose glucocorticoids. Am J Respir Crit Care Med 156: 737–743, 1997.[Abstract/Free Full Text]
  51. Wilder JA, Collie DD, Wilson BS, Bice DE, Lyons CR, and Lipscomb MF. Dissociation of airway hyperresponsiveness from immunoglobulin E and airway eosinophilia in a murine model of allergic asthma. Am J Respir Cell Mol Biol 20: 1326–1334, 1999.[Abstract/Free Full Text]
  52. Yokomizo T, Izumi T, Chang K, Takuwa Y, and Shimizu T. A G-protein-coupled receptor for leukotriene B4 that mediates chemotaxis. Nature 387: 620–624, 1997.[CrossRef][Medline]
  53. Zhou EM and Kisil FT. Antibody responses to allergen Lol pIV are suppressed following adoptive transfer of B lymphocytes from the internal image anti-idiotypic antibody-treated mice. Cell Immunol 165: 77–83, 1995.[CrossRef][Web of Science][Medline]
  54. Zuberi RI, Apgar JR, Chen SS, and Liu FT. Role for IgE in airway secretions: IgE immune complexes are more potent inducers than antigen alone of airway inflammation in a murine model. J Immunol 164: 2667–2673, 2000.[Abstract/Free Full Text]



This article has been cited by other articles:


Home page
 Am. J. Respir. Cell Mol. Bio.Home page
N. Miyahara, H. Ohnishi, S. Miyahara, K. Takeda, S. Matsubara, H. Matsuda, M. Okamoto, J. E. Loader, A. Joetham, M. Tanimoto, et al.
Leukotriene B4 Release from Mast Cells in IgE-Mediated Airway Hyperresponsiveness and Inflammation
Am. J. Respir. Cell Mol. Biol., June 1, 2009; 40(6): 672 - 682.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
290/1/L170    most recent
00212.2005v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (4)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Medoff, B. D.
Right arrow Articles by Luster, A. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Medoff, B. D.
Right arrow Articles by Luster, A. D.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2006 by the American Physiological Society.